UACC using targeted radiation therapies to reduce patient risk

University of Arizona Cancer Center physicians are on the cutting edge of developing safer, more targeted therapies for breast cancer patients undergoing radiation therapy for their disease.

With recent studies showing potentially dangerous links between breast cancer patients who undergo radiation therapy and develop heart problems later in life, the development of targeted therapies is among the top priorities of today’s radiation oncologists.

Baldassarre Stea, MD, PhD, FASTRO, is the UA Cancer Center’s Head of Radiation Oncology. The department uses a technique known as respiratory gating, a technology that enables clinicians to track a tumor’s position in relation to the patient’s respiratory cycle. This targeted therapy technique spares the heart and focuses the radiation beam specifically on cancerous cells.

“We’ve been proactive when it comes to minimizing a patient’s heart risk,” Dr. Stea said. “We’ve made quantum leaps in this technology, compared to where it used to be.”

The radiation oncology team has developed a method of using the Varian® Real-time Position Management (RPM) system in conjunction with video goggles. This system increases treatment delivery accuracy, while maintaining patient comfort.

“For close to two years now, we’ve been the only cancer treatment center in Southern Arizona using this technology,” Dr. Stea added.

The RPM system allows for more accurate imaging and treatment of tumors in high-risk areas, including the breast. Using an infrared camera, the system accurately measures the patient’s respiratory pattern by tracking a small reflective marker placed on the patient’s chest. The patient is also fitted with video goggles, which provide a real-time image of his or her respiratory cycle. Coupled with the imaging and treatment equipment, the RPM system electronically triggers the radiation beam only when the patient is in the correct respiratory position.

Using this method, the clinicians are able to identify a tumor’s position in relation to the patient's respiratory cycle, which helps to dramatically reduce the dose to the heart in breast treatments.

Throughout the treatment, the patient is able to visualize the respiratory gating window displayed on the goggles and holds his or her breath when in the correct position. If the patient breathes outside of the determined threshold, the system automatically turns off the treatment beam. Visual feedback throughout the treatment gives the patient freedom to manage their respiration while being treated effectively.